The present invention pertains to the field of database generation, maintenance and modification. More particularly, the present invention relates to a method of modifying database object structures in accordance with changes made to metadata objects describing the database objects.
Relational databases are advantageous in that the duplication of information or data within a relational database is limited by defining relationships between data records (or rows) in a number of data objects. Accordingly, the updating of the actual data within the database is simplified as the occurrence of the duplicate data items within the database is minimized. However, the modification of the structure (as opposed to the database data) of a populated database, for example by the modification of data formats, types or lengths or by the addition of columns to a table within the database, is nonetheless problematic, and typically requires the intervention of a database expert. For example, a particular data item (e.g., an amount) may be defined to have a particular format that requires modification (e.g., from the 999.9999 format to the 99999.99 format). As such a data item may be referenced by a number of the dependent tables and procedures within a database, such a modification to a populated database structure typically requires a database expert to make corresponding modifications to all dependent tables and procedures. The location, identification and modification of such dependent objects (e.g., table, procedure and view objects) must manually be performed, and is thus time consuming and inefficient. Further, the modification task is made difficult by the presence of data within such dependent objects. The problem is exasperated when massive databases are employed in complex systems, such as Enterprise Resource Planning (ERP) systems.
According to the invention, there is provided a method of modifying a database structure. Metadata, which describes the database structure, is modified. The database structure is then automatically modified to conform to the modified metadata.
Other features of the present invention will be apparent from the accompanying drawings and from the detailed description that follows.